1. Field of the Invention
The present invention relates to routing telephony communications. More specifically, the present invention relates to re-routing telephony communications over a data network or over a public switched telephone network (PSTN).
2. Description of Related Art
Two classes of conventional systems have been designed to route typical telephony communications through data networks. The first class of conventional routing systems uses "re-dialers". Re-dialers re-route specific calls through a separate transmission path, e.g., a data network, using a real-time or store-and-forward transport mechanism. Typically, the re-dialers are placed between an originating telephony device (most typically a fax machine) and a public switched telephone network (PSTN) or private branch exchange (PBX).
A first class of conventional routing systems is shown schematically in FIG. 1. FIG. 1 illustrates a fax machine 101 connected to a re-dialer 102. The re-dialer is connected to a PSTN point of presence (POP) 201. The re-dialer 102 is also connected to a wide area network (WAN) POP 301. The PSTN POP 201 serves as a gateway to the PSTN 200. The WAN POP 301 serves as a gateway to the WAN 300. A fax machine 103 can receive a fax transmission from fax machine 101. It should be noted that, in the general sense, the fax machine 103 can transmit a fax as well as receive a fax. The fax machine 103 receives the fax from either a PSTN POP 202 (if the fax is transmitted over the PSTN 200) or a WAN POP 302 (if the fax is transmitted over the WAN 300). The PSTN POP 202 is similar in operation to PSTN POP 201. The WAN POP 302 is similar in operation to the WAN POP 301.
The re-dialer 102 can re-route any fax call through a data network rather than through a PSTN 200. As used herein a data network can be a private wide-area network, a shared wide-area network such as could be provided by a value-added network service provider, an intranet, the internet, or any combination of these. Such a data network is showing in FIG. 1 as WAN 300. Re-routing can be based on the phone number dialed or other telephony condition (e.g., receiver busy). If re-routed, a fax machine 101 communicates with a fax machine 103 through the data network rather than through the PSTN 200. The communication can be conducted in real-time or can be delayed, e.g., by store and forward delivery. However, this first class of conventional routing systems requires a re-dialer for each telephone device, which is a significant drawback.
The second class of conventional routing systems provides real-time voice communications from and to computer systems which have analog-to-data hardware and appropriate software. Though currently popular on the Internet, the second class of conventional routing systems can be implemented on any data network. The second class of conventional routing systems is shown schematically in FIG. 2. A workstation user 104 communicates with a workstation user 105 through the WAN 300. Recent modifications to the second class of conventional routing systems allow the receiver of the phone call, the user 105, to use a telephone rather than a computer workstation.
The primary drawback to the second class of conventional routing systems is that the call originator must change his or her telephony interface. In the case of voice calls, for example, the change requires that the call originator speak and listen through a computer system instead of through a telephone. A fairly straightforward modification of the second class of conventional routing systems is to have the call originator dial directly into a WAN POP 301 from a telephone. This modification also requires the user to dial one number for connection, identify himself or herself for authorization purposes, and then identify the receiver's address (i.e., workstation identifier or telephone number.) i.e., Thus, the modification requires the user to change the user's interface.
Neither class of conventional routing systems addresses the most typical implementation of business communications, which includes multiple call originators initiating (currently) telephony-based communications through a PBX. Any solution that requires independent devices for each call originator presents an installation, maintenance, and management challenge that is unrealistic for most organizations. Organizations cannot as easily cost justify a multiple device solution. Furthermore, system administrators have less control over the traffic generated by users who have the option of using or not using a re-routing device at their call origination site. A solution is needed that provides a single point of installation, maintenance and management. This centralized solution is more cost-effective, and lessens user control over routing decisions.
Moreover, any solution that requires a modification of an existing user interface presents a training and acceptance challenge. Users have shown time and again that a drastic change in their communication interface is unacceptable, regardless of the cost-savings that may be realized. For example, MCI was unable to compete successfully against AT&T for long distance telephone traffic when a user had to (a) dial an MCI access number, (b) authenticate himself or herself, and then (c) identify the called party's phone number. MCI was finally able to compete successfully only after their long distance services were allowed to be accessed in the same way that AT&T's long distance services were accessed, i.e., through direct 1+dialing. A solution that involves using a data network based transport instead of PSTN-based transport must similarly be implemented without modification to the user interface.